Conveyor wearing shoes



y 1964 w. F. JOHNSTON ETAL 3,140,774

COVEYOR WEARING SHOES Filed May 16, 1962 2 Sheets-Sheet 1 FIG. I.

y 14, 1964 w; F. JOHNSTON ETAL 3,140,774

COVEYOR WEARING SHOES 2 Sheets-Sheet 2 Filed May 16, 1962 FIG. 3.

FIG. 5.

United States Patent 3,140,774 CONVEYOR WEARING SHOES William F. Johnston, Delafield, Thomas J. Stencel, Milwaukee, and Arnold H. Sobczak, New Berlin, Wis.,

assignors to Chain Belt Company, Milwaukee, Wis., a

corporation of Wisconsin Filed May 16, 1962, Ser. No. 195,175 12 Claims. (Cl. 198137) This invention relates to chain operated grit collectors or the like and particularly to the wearing shoes which engage and slide on the spaced parallel tracks provided for the support of the rakes and buckets of the collector.

The amount of wear allowed for each shoe is limited because the clearances allowed between the lip of the rake or bucket and the bottom of the grit collection trough cannot generally be greater than one-quarter of an inch. Accordingly, when that amount of wear has occurred, the shoes must be replaced because continued wear would allow the rake or bucket to scrape the concrete floor of the trough and result in considerable damage.

According to the present invention, each wearing shoe comprises an elongated member of square section and of wear-resistant material and each end of the rake or bucket is provided with a pair of such shoes.

Each shoe has four identical wearing surfaces and a bolt extending lengthwise through the shoe to secure the shoe within a bracket fixed to the end of the rake or bucket. The bolt is readily removed to allow the shoe to be rotated ninety degrees to present successively its four surfaces for sliding on the track. Additionally, the shoes are reversible end-for-end and are interchangeable so thatthe maximum allowable wear from the shoes can be utilized. This allows the shoes to be economically made of one of the several relatively expensive but extremely wear-resistant materials now available.

The bolt holds the side of the shoe in position against an abutment to prevent its rotation. The side, referred to, is recessed and located between the ends of the shoe and is in that way unaffected by the wear of the adjacent surfaces.

The shoes are employed in pairs and also secure the pin securing the rake or bucket to the chain. The pin is disposed between the shoes and its removal is allowed by removal of either shoe.

The drawings furnished herewith illustrate the best mode of carrying out the invention as presently contemplated and set forth hereinafter.

In the drawings:

FIGURE 1 shows a part of a gritcollection channel in vertical longitudinal cross-section. The chain and sprocket mechanism carrying the buckets is shown diagrammatically;

FIG. 2 is a plan view of one end of a bucket moving on the track shown in part. The attachment lug of the chain, not shown, which moves the bucket is broken away and shown projecting away from the bucket;

FIG. 3 is an end elevation of the grit bucket. The chain attachment lug is broken away and sectioned. The pin securing the attachment lug to the bucket is shown between the upper and lower shoes;

FIG. 4 is a front elevation of theend of the bucket shown in FIG. 3; and

FIG. 5 is a perspective view of the bucket with sections The grit collection channel 1 is provided for the flow of raw sewage therethrough with a controlled velocity so that the sand and grit settles on the floor surface 2 of the channel. A minimum velocity is provided so that the organic material including all of the putrescibles of the sewage is carried through the channel. The mechanism for removal of the grit includes parallel chains 3 shown diagrammatically in FIGURE 1 and the series of buckets 4 which are secured to and disposed at spaced intervals between the chains 3. Each bucket 4 moving over floor 5 of channel 1 is disposed so that it opens forwardly and a minimum of clearance is allowed between the floor and the lower lip 6 of the bucket. The rails supporting and guiding the bucket include the lower rail 8 which is cast or embedded in the concrete floor 5 and the hold-down rail 9 which is bolted to each side wall 11 of the channel.

At the end of the channel shown in FIGURE 1, buckets 4 are carried upwardly into the housing 12 mounted on the deck 13 covering the channel. As the chains 3 move over the uppermost sprocket, buckets 4 are inverted to discharge the grit into suitable collection means within the housing.

On the return run of the chain, the chain and buckets are supported above the liquid level of the flow within the channel by a rail 14 secured to each side wall 11 of the channel.

Each end of each bucket is similarly provided with means for sliding on rails 8 and 14 and also for receiving the attachment lug 15 projecting from corresponding links of chains 3.

The upper and lower U-shaped brackets 21 having opposite ends 22 extending upwardly and downwardly, respectively, are welded directly to the end plate 23 of bucket 4. The center sections 24 of brackets 21 are spaced to receive lug 15 therebetween and may be connected by the small vertical plate 25 between sections 24 adjacent to lug 15. Plate 25 is located ahead of lug 15 respecting the forward movement of the bucket and is intended to keep the attachment of the lug to the bucket from becoming tight with material.

The attachment, referred to, is provided by the pin 26 fitting loosely in holes 27 of sections 24 of brackets 21 and the aligned hole in lug 15.

The support of the bucket on the rails is provided by the shoes 31 of rectangular section and of a length to fit between ends 22 of brackets 21.

A shoe 31 is provided for each bracket 21 and is secured by the bolt 32 extending through the aligned holes 33 in ends 22 of the bracket and the longitudinal bore 34 formed in the shoe.

Each shoe may be of cast metal, or molded rubber or plastic, or possibly of wood depending upon the desired period of service expected and the severity or rate of wear. According to the invention, the removal of bolt 32 allows the shoe to be turned ninety degrees or one hundred eighty degrees on its axis to present a new wearing surface until all four sides have been worn. Since the buckets tend to tilt downwardly and forwardly when pushing the grit along floor 5 of the channel, the shoes are unevenly worn and may be reversed end-for-end in the bracket to make full use of the material of the shoe. The shoes which may engage rail 9 and slide on return rails 14 are subject to less wear than the shoes sliding on rails 8 and their interchangeability also extends the use of the shoes.

As mentioned, it is necessary that wearing surfaces must be renewed after only a quarter of an inch of wear because the lip 6 of the bucket must operate within that distance of floor of channel 1. Riveting or adhesively securing a wear resistant material of about that thickness to a core to comprise shoe 31 might be acceptable in some cases. However, some extra material is always required to provide a margin against wear of the core and to accommodate the secureinent means itself. It has been found that the availability of the four sides of the shoe for Wear justifies and makes preferable the molding of the shoe without a core.

The shoes are beveled at each end for normal sliding over any small unevenness in the rail surfaces and also include the recess 35 extending across each side of the shoe midway between the ends thereof. The several recesses 35 of each shoe form a circumferential groove and should have a depth which is slightly greater than the allowable wear of the shoe. The shoe as secured between the ends of bracket 21 may fit against plate 23, if desired. The key 36 fixed to end plate 23 of bucket 4 fits each recess 35 of the shoe and prevents rotation of the shoe on bolt 32 notwithstanding the worn conditions of the adjacent surfaces of the shoe.

The ends of pin 26 project into the adjacent recesses 35 of the shoes 31 so that the shoes normally hold the pin in place therebetween. The removal of either of the bolts 32 and the corresponding shoe, according to whichever is the more accessible, immediately exposes then the projecting end of the pin for its removal. Since the pin may initially have a relatively loose fit in lug 15 and holes 27, normal wear and fretting keeps the pin loose and easily removed. The usual difficulty in removing bolt 32 due to rusting can be encountered and expected. If bolts 32 should become rusted, the removal of the bolt is greatly expedited by its having both ends accessible and on the same side of the chain.

The invention may also be and is equally Well used with the rakes mentioned or other attachments to the chain which are similarly supported for sliding on rails.

Various embodiments of the invention may be employed within the scope of the following claims.

We claim:

1. In a chain and scraper mechanism for a grit collection system including a trough, parallel tracks extending along each side of the trough, endless chains operating over the tracks and having projecting attachment ears at corresponding intervals, and a scraper connected between chains at each interval, each end of the scraper having spaced attachment lugs and a removable pin extending vertically therethrough and through the corresponding ear of the chain for such connection; upper and lower wearing shoes for each end of each scraper, a U-shaped bracket fixed to each end of each scraper for receiving a shoe therebetween, and bolt means associated with each bracket normally securing said shoe therebetween while allowing periodic rotation of the shoe about its axis to present successively its several sides for sliding engagement with the track for the support of the scraper thereon.

2. In a grit collector mechanism including spaced, parallel endless chains having attachment ears opposite each other and a scraper therebetween for operation over upper and lower parallel tracks, means for securing each end of the scraper to the respective attachment ear and for slidably supporting the end of the scraper on the respective upper and lower tracks successively in the upright and the inverted positions comprising a clevis in which the corresponding attachment ear is received and a removable pin extending vertically therethrough and having ends projecting therefrom, a projecting key fixed to the end of the scraper adjacent to and in alignment with each of said projecting ends of said pin, upper and lower wear-resistant, elongated shoes of square cross-section and having a central recess in each of its four sides, and bolt means at each end of each shoe and securing the same in posill tion against the end of the scraper with a key disposed in one of the recesses of the shoe and the adjacent end of said pin extending in a similarly adjacent recess, said shoes serving to retain said pin in said clevis and each of said keys serving to index the corresponding shoe in each of four positions for successively presenting its four wearing surfaces to slideably engage the corresponding track.

3. The invention of claim 2 wherein each shoe is reversible end-for-end to allow both'ends of the shoe to operate successively as the forward end having the greater wear rate due to the direction referred to.

4. In a conveyor comprising a supporting rail and a material moving part movable parallel to said rail, means for slidably supporting said part on said rail comprising a U-shaped bracket fixed to said part and having a bolt extending through the spaced ends of said bracket, an abutment fixed to said part and with respect to said bracket and midway between said ends of the bracket, and a wear-resistant shoe having a longitudinal axial bore through which said bolt extends, said shoe being dimensioned to fit between the ends of said bracket in any of four equally spaced positions of rotation on said bolt to present alternatively four Wearing surfaces to engage the rail referred to, and having four identical sides, each side including a recessed face disposed to engage said abutment in each of said four positions.

5. The invention of claim 4 wherein the shoe is also reversible end for end on said bolt.

6. In a chain conveyor comprising a fixed rail and a scraper movable therealong, means for slidably supporting said scraper on said rail, comprising a projecting key fixed to said scraper, a rectangular wear-resistant shoe having a longtudinal, central bore and a recess extending across each side thereof midway between the ends of the shoe and respectively fitting said key, spaced bracket means fixed to the scraper to receive said shoe therebetween and having holes registering with the bore of the shoe, and means disposed in said registering holes and bore for bolting and holding the shoe against displacement and with said key in any selected recess to present selectively the four corresponding sides of the shoe for sliding on the rail.

7. The invention of claim 6 wherein the shoe is also reversible end for end between said bracket means.

8. In conveyor mechanism comprising a rail and a material transferring device movable along said rail, means for slidably supporting said device on said rail, comprising a shoe having ends and sides of a wear resistant material, and intermediate and end holding brackets for said shoe secured to said device, the intermediate holding brackets comprising an abutment, and the end brackets and ends of said shoe having aligned, interfitting pin connections whereby said shoe may be variously positioned about the axis of said connections to dispose selectively the several sides of said shoe for engagement with the fixed rail, each side of the shoe having a recess of a depth at least equal to that of the expected wear of the shoe and fitting said abutment to secure the shoe in each of said positions.

9. The invention of claim 8 wherein the recesses and abutment are intermediate the ends of the shoe and the shoe is reversible end-for-end.

10. In a chain operated scraper mechanism comprising a fixed rail and a scraper supported for movement on said rail, a shoe having sides of a wear resistant material, and intermediate and end holding brackets for said shoe secured to said scraper, the intermediate holding brackets providing an abutment, and the end brackets and the ends of said shoe having aligned, interfitting pin connections, at least one of said pin connections being removable whereby said shoe may be variously positioned about the axis of said connections to dispose selectively the several sides of said shoe for engagement with the fixed rail, each side of the shoe having a recess of a depth at least equal to t at f he allowable wear of the shoe, and said recesses selectively fitting said abutment to secure the shoe in the respective positions referred to.

11. The invention of claim 10 wherein the recesses and abutment are intermediate the ends of the shoe and the shoe is reversible end-for-end.

12. In a chain operated scraper mechanism comprising a fixed rail and a scraper element supported for movement on said rail, a shoe having sides of a Wear resistant material, and end holding brackets for said shoe secured to said scraper, the end brackets and the ends of said shoe having aligned, interfitting pin connections, at least one of said pin connections being removable to allow said shoe to be variously positioned about the axis of said connections for presenting selectively the several sides of said shoe for engagement with the fixed rail With another of the sides of the shoe abutting the scraper.

No references cited. 

1. IN A CHAIN AND SCRAPER MECHANISM FOR A GRIT COLLECTION SYSTEM INCLUDING A TROUGH, PARALLEL TRACKS EXTENDING ALONG EACH SIDE OF THE TROUGH, ENDLESS CHAINS OPERATING OVER THE TRACKS AND HAVING PROJECTING ATTACHMENT EARS AT CORRESPONDING INTERVALS, AND A SCRAPER CONNECTED BETWEEN CHAINS AT EACH INTERVAL, EACH END OF THE SCRAPER HAVING SPACED ATTACHMENT LUGS AND A REMOVABLE PIN EXTENDING VERTICALLY THERETHROUGH AND THROUGH THE CORRESPONDING EAR OF THE CHAIN FOR SUCH CONNECTION; UPPER AND LOWER WEARING SHOES FOR EACH END OF EACH SCRAPER, A U-SHAPED BRACKET FIXED TO EACH END OF EACH SCRAPER FOR RECEIVING A SHOE THEREBETWEEN, AND BOLT MEANS ASSOCIATED WITH EACH BRACKET NORMALLY SECURING SAID SHOE THEREBETWEEN WHILE ALLOWING PERIODIC ROTATION OF THE SHOE ABOUT ITS AXIS TO PRESENT SUCCESSIVELY ITS SEVERAL SIDES FOR SLIDING ENGAGEMENT WITH THE TRACK FOR THE SUPPORT OF THE SCRAPER THEREON. 